It explains some common principles than can be used in the transmission of safety-relevant messages among participants within a distributed network using fieldbus technology in accordance with the requirements of IEC 61508 series for functional safety. These principles can be used in various industrial applications such as process control, manufacturing automation and machinery. It specifies several functional safety communication profiles based on the communication profiles and protocol layers of the fieldbus technologies in IEC 61784 1, IEC 61784 2 and the IEC 61158 series.